I tend to use quorn mince these days personally...no thinking involved then with draining fat, and I find the taste is better. At 2pp for 100g, it's the ideal solution for dieting I find. But that's just me.
When I have used meat mince, though, I've always drained off the fat, but no idea if it makes any difference to the points. I'd like to think it does, but probably wishful thinking...although if there's all that fat floating around in a dish, maybe it does make a difference. Very confusing.